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0 pointscdavid12y ago0 comments

Actually, I don't think the import * in numpy is anything else than historical artefact. Numpy just happens to be one of the oldest, still widely used python library (considering numpy started as numeric), as you point out. As for import speed, have you considered using lazy import in your script ?

I don't see numpy being integrated in python anytime soon. I don't think it would bring much, and one would have to drop performance enhancement that rely on blas/lapack.

I think installing has improved a lot, and once pip + wheel matures, it should be easy to pip install numpy on windows.

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dalke12y ago

I've asked on the numpy mailing list. The "import * " was a design decision, now irrevocable without breaking existing code.

For examples, from http://mail.scipy.org/pipermail/numpy-discussion/2008-July/0... :

Robert Kern: Your use case isn't so typical and so suffers on the import time end of the balance

Stéfan van der Walt: I.e. most people don't start up NumPy all the time -- they import NumPy, and then do some calculations, which typically take longer than the import time. ... You need fast startup time, but most of our users need quick access to whichever functions they want (and often use from an interactive terminal).

I went back to the topic last year. Currently 25% of the import time is spent building some functions which are then exec'ed. At every single import. I contributed a patch, which has been hanging around for a year. I came back to it last week. I'll be working on an updated patch.

There's also about 7% of the startup time because numpy.testing imports unittest in order to get TestCase, so people can refer to numpy.testing.TestCase. Even though numpy does nothing to TestCase and some of numpy's own unit tests use unittest.TestCase instead. sigh. And there's nothing to be done to improve that case.

Regarding the age - yes, you're right. BTW, parts of PIL started in 1995, making it the oldest widely used package, I think. Do you know of anything older?

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